Designing shapes onto PCB artwork

Brian Hoskins said:

Well analogue Electronics is not my forte, and whilst I'm quite capable of designing an audio amplifier (a crude one at least) I decided that I didn't have time so I bought a cheap amplifier module with an 8R output from Maplin. It's not very powerful, but it fits the bill quite nicely!

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Don't be put off, it's really easy with an IC like the LM386 or TDA7052 (if you want it louder).

You probably only need a gain of 20 for an 8 ohm speaker so this minimal circuit will probably do:
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LM386 Schematic diagrams

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The Craplin amplifier module is probably just a simple audio amplifier IC with a couple of capacitors and resistors. These sorts of things tend to be really overpriced. It probably would have been economical to make your own.

What are you going to use for a speaker?

Although I didn't bother buying them (I've already got plenty of cheap speakers at home) I saw some small speakers in Pound Land a couple of weeks ago. Some were embedded in cardboard and folded up, others were attached to the end of an earphone jack. They would probably be ideal for this kind of thing, form memory (I'm purely talking about the drivers here) the cardboard ones were about 5mm thick and 45mm wide and the earphone jack ones were 25mm wide and 10mm thick. If there's a Pound Land you, I recommend taking a look.

Nigel Goodwin said:

The cold wasn't the biggest problem, the biggest problem was car drivers - even though I had my headlight on all the time you could guarantee at least twice a week someone would pull out in front of you. Good for your reactions though!

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My Dad was always complaining about that, and so I've become extra aware of motorbike riders. If I see one coming up behind I'll hug the kerb a little bit, give him plenty of room to scoot past. I can't say I've never been caught unaware by a motorbike though, because I'm sure I have at one point or other!

Hero999 said:

What are you going to use for a speaker?

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Yeah funny you should mention that. I do have a little collection of speakers in my "stash", and although I could get away with using one of them they're actually a little bit too big to be honest. My collection mainly consists of TV speakers from scrapped units.

Your suggestion sounds far better suited. The sound quality isn't likely to be very good, but really it doesn't have to be - it's not like I'm building a HIFI is it. An inconspicuous size is probably the most desirable quality I'm seeking. I shall check out your suggestions, thanks!

Brian